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2021 JMPSC Sprint Problems/Problem 2

Revision as of 23:44, 10 July 2021 by Oofpirate (talk | contribs)

Problem

Brady has an unlimited supply of quarters ($0.25), dimes ($0.10), nickels ($0.05), and pennies ($0.01). What is the least number (quantity, not type) of coins Brady can use to pay off $$2.78$?

Solution

It is generally best to use the smallest number of coins with the most value, specifically the quarters, for taking away a big chunk of the problem. We are able to fit $11$ quarters, or $$2.75$ into $$2.78$. That only leaves $3$ cents. We cannot put any nickels nor dimes, therefore we require three pennies to get a total of $$2.78$.

The least number of coins Brady can use to pay off $$2.78$ will be $14$ coins.

-OofPirate

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